Volatilomes of human infection

The human volatilome comprises a vast mixture of volatile emissions produced by the human body and its microbiomes. Following infection, the human volatilome undergoes significant shifts, and presents a unique medium for non-invasive biomarker discovery. In this review, we examine how the onset of infection impacts the production of volatile metabolites that reflects dysbiosis by pathogenic microbes. We describe key analytical workflows applied across both microbial and clinical volatilomics and emphasize the value in linking microbial studies to clinical investigations to robustly elucidate the metabolic species and pathways leading to the observed volatile signatures. We review the current state of the art across microbial and clinical volatilomics, outlining common objectives and successes of microbial-clinical volatilomic workflows. Finally, we propose key challenges, as well as our perspectives on emerging opportunities for developing clinically useful and targeted workflows that could significantly enhance and expedite current practices in infection diagnosis and monitoring.

Monitoring of emerging contaminants of concern in the aquatic environment: a review of studies showing the application of effect-based measures

Water scarcity is increasingly a global cause of concern mainly due to widespread changes in climate conditions and increased consumptive water use driven by the exponential increase in population growth. In addition, increased pollution of fresh water sources due to rising production and consumption of pharmaceuticals and organic chemicals will further exacerbate this concern. Although surface water contamination by individual chemicals is often at very low concentration, pharmaceuticals for instance are designed to be efficacious at low concentrations, creating genuine concern for their presence in freshwater sources. Furthermore, the additive impact of multiple compounds may result in toxic or other biological effects that otherwise will not be induced by individual chemicals. Globally, different legislative frameworks have led to pre-emptive efforts which aim to ensure good water ecological status. Reports detailing the use and types of effect-based measures covering specific bioassay batteries that can identify specific mode of actions of chemical pollutants in the aquatic ecosystem to evaluate the real threat of pollutants to aquatic lives and ultimately human lives have recently emerged from monitoring networks such as the NORMAN network. In this review, we critically evaluate some studies within the last decade that have implemented effect-based monitoring of pharmaceuticals and organic chemicals in aquatic fauna, evaluating the occurrence of different chemical pollutants and the impact of these pollutants on aquatic fauna with special focus on pollutants that are contaminants of emerging concern (CEC) in urban wastewater. A critical discussion on studies that have used effect-based measures to assess biological impact of pharmaceutical/organic compound in the aquatic ecosystem and the endpoints measurements employed is presented. The application of effect-based monitoring of chemicals other than assessment of water quality status is also discussed.

An Investigation of Stability and Species and Strain-Level Specificity in Bacterial Volatilomes

Microbial volatilomics is a rapidly growing field of study and has shown great potential for applications in food, farming, and clinical sectors in the future. Due to the varying experimental methods and growth conditions employed in microbial volatilomic studies as well as strain-dependent volatilomic differences, there is limited knowledge regarding the stability of microbial volatilomes. Consequently, cross-study comparisons and validation of results and data can be challenging. In this study, we investigated the stability of the volatilomes of multiple strains of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli across three frequently used nutrient-rich growth media. Volatilomic stability was assessed based on media-, time- and strain-dependent variation across the examined bacterial volatilomes. Strain-level specificity of the observed volatilomes of E. coli and P. aeruginosa strains was further investigated by comparing the emission of selected compounds at varying stages of cell growth. Headspace solid phase microextraction (HS-SPME) sampling coupled with gas chromatography mass spectrometry (GC-MS) was used to analyze the volatilome of each strain. The whole volatilomes of the examined strains demonstrate a high degree of stability across the three examined growth media. At the compound-level, media dependent differences were observed particularly when comparing the volatilomes obtained in glucose-containing brain heart infusion (BHI) and tryptone soy broth (TSB) growth media with the volatilomes obtained in glucose-free Lysogeny broth (LB) media. These glucose-dependent volatilomic differences were primarily seen in the emission of primary metabolites such as alcohols, ketones, and acids. Strain-level differences in the emission of specific compounds in E. coli and P. aeruginosa samples were also observed across the media. These strain-level volatilomic differences were also observed across varying phases of growth of each strain, therefore confirming that these strains had varying core and accessory volatilomes. Our results demonstrate that, at the species-level, the examined bacteria have a core volatilome that exhibits a high-degree of stability across frequently-used growth media. Media-dependent differences in microbial volatilomes offer valuable insights into identifying the cellular origin of individual metabolites. The observed differences in the core and accessory volatilomes of the examined strains illustrate the complexity of microbial volatilomics as a study while also highlighting the need for more strain-level investigations to ultimately elucidate the whole volatilomic capabilities of microbial species in the future.

63 The “Brighton Connector”: A Simple, Reproducible and Cost-Effective Technique for Bilateral Antegrade Cerebral Perfusion During Aortic Arch Surgery

Aim

Surgery of the aortic arch presents significant technical and physiological challenges. Selective antegrade cerebral perfusion (SACP) during arch surgery has been shown to improve mortality and neurological outcomes in these patients. At our centre, we aimed to develop a safe, reliable, and cost-effective technique to provide bilateral antegrade cerebral perfusion without the need of another pump head.

Method

We developed our system using equipment that is included in the accessory packaging for the Sorin Xtra cell saver system, which is readily available in cardiac surgical units nationwide, but often discarded as it is not required. An EOPA arterial return cannula and the TRUE FLOW RDB SACP cannula were joined using our novel connection.

Results

A single surgeon has used the “Brighton Connector” for 6 patients in the last two years. All patients made a satisfactory recovery with a 0% rate of mortality or permanent neurological deficit.

Conclusions

All components in our circuit are already approved for use in cardiac theatres, and the connection tubing would normally be discarded, making our method cost neutral. We demonstrate through a case series that mortality and neurological outcomes are good and comparable with other techniques.

64 Seizing an Opportunity: Setting Up A Virtual Wetlab During the COVID19 Pandemic

Aim

The COVID19 pandemic has negatively impacted surgical training across the globe. In the UK, educational events and training days were cancelled for trainees at all levels. However, these unusual times provide opportunity to develop novel teaching methods. Our aim was to design a “virtual cardiac surgery wetlab” that allows real-time skills training.

Method

With support from industry partners Edwards Lifesciences, Wetlab and Connexon365 (Webinar Hosting Platform) all the necessary materials were distributed. A package was sent to trainer and trainees that included microinstruments, sutures, synthetic vessels and valve models, high-definition camera, along with printed instructions and video to outline set-up of the rig. Trainees only need to provide is a computer. A consultant surgeon demonstrated how to perform a coronary anastomosis and aortic valve replacement and was then able to supervise trainees and provide real-time feedback using the online platform.

Results

Feedback from trainer and trainees has shown that the system is an easy-to-set-up, effective training tool for teaching cardiac surgery skills including coronary anastomosis and valve surgery. The online platform enabled good vision and engagement between trainer and trainee and also enabled recording of the session. Distributing all of the materials nationwide means the virtual wetlab can take place anywhere, including in the comfort of home, for both trainee and trainer.

Conclusions

Surgical skills training can still take place effectively in the absence of “real life” wetlabs. Given the current COVID19 pandemic continues to interrupt traditional surgical teaching, this method has potential to be adopted nationwide to minimise the disruption.

A review of pharmaceutical occurrence and pathways in the aquatic environment in the context of a changing climate and the COVID-19 pandemic

Active pharmaceutical ingredients (APIs) are increasingly being identified as contaminants of emerging concern (CECs). They have potentially detrimental ecological and human health impacts but most are not currently subject to environmental regulation. Addressing the life cycle of these pharmaceuticals plays a significant role in identifying the potential sources and understanding the environmental impact that pharmaceuticals may have in surface waters. The stability and biological activity of these "micro-pollutants" can lead to a pseudo persistence, with ensuing unknown chronic behavioural and health-related effects. Research that investigates pharmaceuticals predominantly focuses on their occurrence and effect within surface water environments. However, this review will help to collate this information with factors that affect their environmental concentration. This review focuses on six pharmaceuticals (clarithromycin, ciprofloxacin, sulfamethoxazole, venlafaxine, gemfibrozil and diclofenac), chosen because they are heavily consumed globally, have poor removal rates in conventional activated sludge wastewater treatment plants (CAS WWTPs), and are persistent in the aquatic environment. Furthermore, these pharmaceuticals are included in numerous published prioritisation studies and/or are on the Water Framework Directive (WFD) "Watch List" or are candidates for the updated Watch List (WL). This review investigates the concentrations seen in European Union (EU) surface waters and examines factors that influence final concentrations prior to release, thus giving a holistic overview on the source of pharmaceutical surface water pollution. A period of 10 years is covered by this review, which includes research from 2009-2020 examining over 100 published studies, and highlighting that pharmaceuticals can pose a severe risk to surface water environments, with each stage of the lifecycle of the pharmaceutical determining its concentration. This review additionally highlights the necessity to improve education surrounding appropriate use, disposal and waste management of pharmaceuticals, while implementing a source directed and end of pipe approach to reduce pharmaceutical occurrence in surface waters.

Pilot Scale Study: First Demonstration of Hydrophobic Membranes for the Removal of Ammonia Molecules from Rendering Condensate Wastewater

Hydrophobic membrane contactors represent a promising solution to the problem of recycling ammoniacal nitrogen (N-NH₄) molecules from waste, water or wastewater resources. The process has been shown to work best with wastewater streams that present high N-NH₄ concentrations, low buffering capacities and low total suspended solids. The removal of N-NH₄ from rendering condensate, produced during heat treatment of waste animal tissue, was assessed in this research using a hydrophobic membrane contactor. This study investigates how the molecular composition of rendering condensate wastewater undergo changes in its chemistry in order to achieve suitability to be treated using hydrophobic membranes and form a suitable product. The main objective was to test the ammonia stripping technology using two types of hydrophobic membrane materials, polypropylene (PP) and polytetrafluoroethylene (PTFE) at pilot scale and carry out: (i) Process modification for NH₃ molecule removal and (ii) product characterization from the process. The results demonstrate that PP membranes are not compatible with the condensate waste as it caused wetting. The PTFE membranes showed potential and had a longer lifetime than the PP membranes and removed up to 64% of NH₃ molecules from the condensate waste. The product formed contained a 30% concentrated ammonium sulphate salt which has a potential application as a fertilizer. This is the first demonstration of hydrophobic membrane contactors for treatment of condensate wastewater.

Thinking About the Nerve Impulse: The Prospects for the Development of a Comprehensive Account of Nerve Impulse Propagation

Currently, a scientific debate is ongoing about modeling nerve impulse propagation. One of the models discussed is the celebrated Hodgkin-Huxley model of the action potential, which is central to the electricity-centered conception of the nerve impulse that dominates contemporary neuroscience. However, this model cannot represent the nerve impulse completely, since it does not take into account non-electrical manifestations of the nerve impulse for which there is ample experimental evidence. As a result, alternative models of nerve impulse propagation have been proposed in contemporary (neuro)scientific literature. One of these models is the Heimburg-Jackson model, according to which the nerve impulse is an electromechanical density pulse in the neural membrane. This model is usually contrasted with the Hodgkin-Huxley model and is supposed to potentially be able to replace the latter. However, instead of contrasting these models of nerve impulse propagation, another approach integrates these models in a general unifying model. This general unifying model, the Engelbrecht model, is developed to unify all relevant manifestations of the nerve impulse and their interaction(s). Here, we want to contribute to the debate about modeling nerve impulse propagation by conceptually analyzing the Engelbrecht model. Combining the results of this conceptual analysis with insights from philosophy of science, we make recommendations for the study of nerve impulse propagation. The first conclusion of this analysis is that attempts to develop models that represent the nerve impulse accurately and completely appear unfeasible. Instead, models are and should be used as tools to study nerve impulse propagation for varying purposes, representing the nerve impulse accurately and completely enough to achieve the specified goals. The second conclusion is that integrating distinct models into a general unifying model that provides a consistent picture of nerve impulse propagation is impossible due to the distinct purposes for which they are developed and the conflicting assumptions these purposes often require. Instead of explaining nerve impulse propagation with a single general unifying model, it appears advisable to explain this complex phenomenon using a ‘mosaic’ framework of models in which each model provides a partial explanation of nerve impulse propagation.

Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

OBJECTIVE

There are variable reports of risk of concordance for progression to islet autoantibodies and type 1 diabetes in identical twins after one twin is diagnosed. We examined development of positive autoantibodies and type 1 diabetes and the effects of genetic factors and common environment on autoantibody positivity in identical twins, nonidentical twins, and full siblings.

RESEARCH DESIGN AND METHODS

Subjects from the TrialNet Pathway to Prevention Study (N = 48,026) were screened from 2004 to 2015 for islet autoantibodies (GAD antibody [GADA], insulinoma-associated antigen 2 [IA-2A], and autoantibodies against insulin [IAA]). Of these subjects, 17,226 (157 identical twins, 283 nonidentical twins, and 16,786 full siblings) were followed for autoantibody positivity or type 1 diabetes for a median of 2.1 years.

RESULTS

At screening, identical twins were more likely to have positive GADA, IA-2A, and IAA than nonidentical twins or full siblings (all P < 0.0001). Younger age, male sex, and genetic factors were significant factors for expression of IA-2A, IAA, one or more positive autoantibodies, and two or more positive autoantibodies (all P ≤ 0.03). Initially autoantibody-positive identical twins had a 69% risk of diabetes by 3 years compared with 1.5% for initially autoantibody-negative identical twins. In nonidentical twins, type 1 diabetes risk by 3 years was 72% for initially multiple autoantibody-positive, 13% for single autoantibody-positive, and 0% for initially autoantibody-negative nonidentical twins. Full siblings had a 3-year type 1 diabetes risk of 47% for multiple autoantibody-positive, 12% for single autoantibody-positive, and 0.5% for initially autoantibody-negative subjects.

CONCLUSIONS

Risk of type 1 diabetes at 3 years is high for initially multiple and single autoantibody-positive identical twins and multiple autoantibody-positive nonidentical twins. Genetic predisposition, age, and male sex are significant risk factors for development of positive autoantibodies in twins.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Adolescents and young adult cancer survivors: exercise habits, quality of life and physical activity preferences

INTRODUCTION

Given the decades of survivorship for adolescent and young adult (AYA) cancer survivors, it is important to promote behaviours that enhance physical and mental well-being and quality of life (QoL). The purpose of this study was to explore the exercise programming preferences and information needs of AYA survivors and to examine the impact of a cancer diagnosis on physical activity behavior and QoL.

METHODS

Participants aged 15-25 years at time of diagnosis and referred to a specialist AYA cancer service between January 2008 and February 2012 were recruited. Eligible participants were mailed a self-administered questionnaire assessing demographic and disease-related information, physical activity levels over time and exercise information preferences. QoL was measured using the Assessment of Quality of Life-6D (AQoL-6D).

RESULTS

Seventy-four (response rate 52 %) participants completed the questionnaire. The mean age was 23 years with 54 % female, with prevalent diagnoses included hematological malignancy (45 %) and sarcoma (24 %). Results indicated a significant reduction in the average minutes of physical activity post diagnosis (p =< 0.001) and during treatment (p = < 0.001). AYA who met public health physical activity guidelines (n = 36) at questionnaire completion had significantly higher QoL than those not meeting the guidelines (n = 38) (median (Mdn) = 0.87, interquartile range (IQR) = 0.73 to 0.98 and Mdn = 0.81, IQR = 0.57 to 0.93, respectively; p = 0.034). Most participants wanted exercise information at some point after diagnosis (85 %) but many did not receive any information (45 %).

CONCLUSIONS

Findings suggest that AYA with cancer experience a significant impact on physical activity levels and QoL. Moreover, survivors experience considerable difficulty returning to premorbid levels of activity. Our study suggests that interventions promoting physical activity and healthy lifestyle behaviours would be well accepted within this population and may be essential to improve their long-term health and QoL during survivorship.

Metastasis and Circulating Tumor Cells

Cancer is a prominent cause of death worldwide. In most cases, it is not the primary tumor which causes death, but the metastases. Metastatic tumors are spread over the entire human body and are more difficult to remove or treat than the primary tumor. In a patient with metastatic disease, circulating tumor cells (CTCs) can be found in venous blood. These circulating tumor cells are part of the metastatic cascade. Clinical studies have shown that these cells can be used to predict treatment response and their presence is strongly associated with poor survival prospects. Enumeration and characterization of CTCs is important as this can help clinicians make more informed decisions when choosing or evaluating treatment. CTC counts are being included in an increasing number of studies and thus are becoming a bigger part of disease diagnosis and therapy management. We present an overview of the most prominent CTC enumeration and characterization methods and discuss the assumptions made about the CTC phenotype. Extensive CTC characterization of for example the DNA, RNA and antigen expression may lead to more understanding of the metastatic process.

Native gel electrophoresis of human telomerase distinguishes active complexes with or without dyskerin

Telomeres, the ends of linear chromosomes, safeguard against genome instability. The enzyme responsible for extension of the telomere 3′ terminus is the ribonucleoprotein telomerase. Whereas telomerase activity can be reconstituted in vitro with only the telomerase RNA (hTR) and telomerase reverse transcriptase (TERT), additional components are required in vivo for enzyme assembly, stability and telomere extension activity. One such associated protein, dyskerin, promotes hTR stability in vivo and is the only component to co-purify with active, endogenous human telomerase. We used oligonucleotide-based affinity purification of hTR followed by native gel electrophoresis and in-gel telomerase activity detection to query the composition of telomerase at different purification stringencies. At low salt concentrations (0.1 M NaCl), affinity-purified telomerase was ‘supershifted’ with an anti-dyskerin antibody, however the association with dyskerin was lost after purification at 0.6 M NaCl, despite the retention of telomerase activity and a comparable yield of hTR. The interaction of purified hTR and dyskerin in vitro displayed a similar salt-sensitive interaction. These results demonstrate that endogenous human telomerase, once assembled and active, does not require dyskerin for catalytic activity. Native gel electrophoresis may prove useful in the characterization of telomerase complexes under various physiological conditions.

The interaction between EAP30 and ELL is modulated by MCM2

ELL-associated protein 30 (EAP30) was initially characterized as a component of the Holo-ELL complex, which contains the elongation factor ELL. Both ELL and Holo-ELL stimulate RNA pol II elongation in vitro. However, ELL and not Holo-ELL inhibits RNA pol II initiation. It is not clear how these two discrete functions of ELL are regulated. Here we report that mini-chromosome maintenance 2 (MCM2) binds to EAP30 and show that MCM2 competes with ELL for binding to EAP30 thus potentially modulating the stability of Holo-ELL.

A model of personality change after traumatic brain injury and the development of the Brain Injury Personality Scales

OBJECTIVE

The aims of this study were to develop models of personality change after traumatic brain injury (TBI) based on information provided by the TBI survivor and a significant other (SO), and to compare the models generated from the two different sources of information.

METHODS

Individuals with and without TBI and an SO were interviewed separately about their current personality. The SOs were also interviewed about the personality of the TBI survivor before the injury. A subset of TBI survivors and their SOs were interviewed twice to assess test-retest reliability. Items which were not associated with personality change after TBI, which could not be measured reliably or which did not contribute to the model, were excluded.

RESULTS

Of the 123 original items, 29 items from the interview with the survivor and 31 items from the interview with the SO were retained to form the Brain Injury Personality Scales. Separate factor analyses of ratings from each interview (survivor and SO) resulted in seven first order factors. The second order factor analyses for each interview resulted in four factors. Concordance between the information obtained from the two interviews was low.

CONCLUSIONS

The information obtained from the interviews with the TBI survivors and the SOs produced two models with a similar structure: three superordinate factors of personality items (affective regulation, behavioural regulation and engagement) and one superordinate factor of items relevant to mental state (restlessness and range of thought). Despite the similarity in structure, the content of the information obtained from the two interviews was different.

Neofunctionalization in vertebrates: the example of retinoic acid receptors

Understanding the role of gene duplications in establishing vertebrate innovations is one of the main challenges of Evo-Devo (evolution of development) studies. Data on evolutionary changes in gene expression (i.e., evolution of transcription factor-cis-regulatory elements relationships) tell only part of the story; protein function, best studied by biochemical and functional assays, can also change. In this study, we have investigated how gene duplication has affected both the expression and the ligand-binding specificity of retinoic acid receptors (RARs), which play a major role in chordate embryonic development. Mammals have three paralogous RAR genes—RARα, β, and γ—which resulted from genome duplications at the origin of vertebrates. By using pharmacological ligands selective for specific paralogues, we have studied the ligand-binding capacities of RARs from diverse chordates species. We have found that RARβ-like binding selectivity is a synapomorphy of all chordate RARs, including a reconstructed synthetic RAR representing the receptor present in the ancestor of chordates. Moreover, comparison of expression patterns of the cephalochordate amphioxus and the vertebrates suggests that, of all the RARs, RARβ expression has remained most similar to that of the ancestral RAR. On the basis of these results together, we suggest that while RARβ kept the ancestral RAR role, RARα and RARγ diverged both in ligand-binding capacity and in expression patterns. We thus suggest that neofunctionalization occurred at both the expression and the functional levels to shape RAR roles during development in vertebrates.

In eukaryotic organisms, each gene is a stretch of DNA composed of control regions that bind transcription factors and coding regions that transcribe the mRNA that is later translated into proteins. At the molecular level, changes in control regions can affect the time and place at which a protein is synthesized, whereas changes in the coding region can alter the protein's function. Retinoic acid receptors (RARs) are chordate-specific transcription factors which, upon binding the natural morphogen retinoic acid, bind to and activate transcription from target genes. Here, the authors show how the ligand specificity of RARs has changed during vertebrate evolution in parallel with changes in expression. Through functional characterization of the RARs from several vertebrates, the chordate amphioxus, and the reconstructed ancestral RAR sequence, the authors show that of the three vertebrate RARs, RARβ has retained the ancestral characteristics in terms of both function and expression, while RARα and γ have evolved by acquiring new functions, both new binding specificity and new expression patterns. Thus both types of evolution have been important in the diversification of vertebrate RARs.

Consistent and stable expression of the nptII, uidA and bar genes in transgenic Pinus radiata after Agrobacterium tumefaciens-mediated transformation using nurse cultures

An Agrobacterium tumefaciens-mediated transformation protocol has been developed for embryogenic cell cultures of Pinus radiata. Transgenic lines were only produced when embryogenic tissue was placed on nurse tissue during the Agrobacterium co-cultivation and recovery stages of the procedure. Plantlets were regenerated via somatic embryogenesis from ten of the 11 transgenic lines tested and at least 20 of each line were planted in a GMO glasshouse. Expression of the nptII, uidA and bar genes in up to ten plants of each individual transgenic line was evaluated by molecular, biochemical and functional analysis. As expected, expression of the nptII gene varied among the ten lines, while within ten replicates of the same line, nptII expression appeared to be consistent, with the exception of one line, K3. Likewise, the level of GUS activity varied among transgenic lines, but was relatively consistent in plants derived from the same tissue, except for two lines, G4 and G5. Moreover, similar absolute values and pattern of gene expression of uidA was observed in the transgenic plants, for two consecutive years. Plantlets from eight lines survived a spray treatment with the equivalent of 2 kg/ha and 4 kg/ha of the commercial formulation Buster, whereas non-transformed controls died. Southern hybridisation analysis of embryogenic tissue and green needle tissue from putative transgenic lines demonstrated a relatively low number of gene insertions (from one to nine) of both the bar and nptII genes in the nine transgenic lines tested.

Two forms of RNA polymerase II holoenzyme display different abundance during the cell cycle

We analyzed the composition and abundance of two forms of RNA polymerase II (pol II) holoenzyme in synchronized HeLa cells. We did not detect significant changes in pol II holoenzyme composition, but we noticed differences in the abundance of the two complexes at different stages of the cell cycle. Summarized data from several independent experiments demonstrate that pol II holoenzyme, which is purified by GST-TFIIS affinity chromatography, is more abundant during G1/S and S phases. Another form of pol II holoenzyme, which is purified by anti-CDK7 antibodies, shows relatively higher amounts in G2/M and early G1 phases.

Distinct parts of minichromosome maintenance protein 2 associate with histone H3/H4 and RNA polymerase II holoenzyme

Minichromosome maintenance (MCM) proteins are part of the replication licensing factor (RLF-M), which limits the initiation of DNA replication to once per cell cycle. We have previously reported that higher order complexes of mammalian pol II and general pol II transcription factors, referred to as pol II holoenzyme, also contain MCM proteins. In the present study we have analyzed in detail the interaction between MCM2 and pol II holoenzyme. N- and C- terminal deletions were introduced into epitope-tagged MCM2 and the truncated proteins were transiently expressed in 293 cells. Affinity chromatography was used to purify RNA pol II holoenzyme and histone binding MCM complexes. We found that amino acids 168-230 of MCM2 are required for its binding to pol II holoenzyme in vivo. We also showed that bacterially expressed amino acids 169-212 of MCM2 associate with pol II and several general transcription factors in vitro. Point mutations within the 169-212 domain of MCM2 disrupted its interaction with pol II holoenzyme both in vitro and in vivo. This region is distinct from the previously characterized histone H3 binding domain of MCM2.

Structure-based design of non-peptide HIV protease inhibitors

A number of structurally novel P2-ligands have been designed and synthesized. Incorporation of these ligands in the (R)-(hydroxyethyl)sulfonamide isostere provided a series of potent non-peptidyl HIV protease inhibitors.

Results from the low level mercury sorbent test at the Oak Ridge Y-12 Plant in Tennessee

A mercury sorbent test was performed near the headwaters of the Upper East Fork Poplar Creek at the Oak Ridge Y-12 Plant in Tennessee. The sorbents SIR-200 (ResinTech), Keyle:X (SolmeteX), and GT-73 (Rohm and Haas) were the best materials tested for low level mercury removal. Each of these sorbents has a thiol-based active site. None of the tested sorbents reduced the mercury concentration to less than the existing 12 ng/l NPDES limit. For this small scale test, SIR-200, Keyle:X, and GT-73 reduced the mercury concentration to less than 51 ng/l, which is a regulatory treatment goal. The other sorbents tested, including granular activated carbon (Filtrasorb 300), did not reduce the mercury concentration below 51 ng/l at any tested flow up to 5 bed volumes per minute. Because of the cost and large volume of sorbent, a wastewater treatment plant for this stream would be prohibitively expensive to construct and maintain.

Structure based design: novel spirocyclic ethers as nonpeptidal P2-ligands for HIV protease inhibitors

A series of novel spirocyclic ethers were designed to function as nonpeptidal P2-ligands for HIV-1 protease inhibitors. Incorporation of designed ligands in the (R)-(hydroxyethylamino)sulfonamide isostere afforded potent HIV protease inhibitors.

Increasing cultural competence with the Latino community

There is growing recognition among health professionals that being familiar with the culture of a particular group and developing effective partnerships to involve group members in the production of their own health are essential strategies to promote health. Moreover, it is increasingly recognized that providing health care services that are culturally sensitive can result in improved health status for clients. This article describes selected Latino cultural customs that can enhance a nurse's ability to work sensitively and effectively with this ethnic group. Creative strategies to increase the cultural competence of nurses involved in primary care settings are also presented.

Potent HIV protease inhibitors incorporating high-affinity P2-ligands and (R)-(hydroxyethylamino)sulfonamide isostere

Design and synthesis of a series of very potent nonpeptide HIV protease inhibitors are described. The inhibitors are derived from novel high affinity P2-ligands and (R)-(hydroxyethylamino)sulfonamide isostere.

Barriers to Treatment Participation Scale: evaluation and validation in the context of child outpatient treatment

This study examined barriers that families experience during treatment and the role these barriers play in participation and completion of therapy. We developed the Barriers to Treatment Participation Scale and evaluated performance among children (N = 260, ages 3-13) and families referred for outpatient treatment. The results indicated that: (a) the scale yielded high levels of internal consistency; (b) the experience of barriers to participation, whether rated by parents or therapists, predicted higher rates of dropping out of treatment, fewer weeks in treatment, and higher rates of cancelled appointments and not showing up for sessions; (c) the perception of barriers was distinguishable from several family, parent, and child characteristics assessed at intake and the experience of critical life events during treatment; and (d) perceived barriers added significant information in predicting participation in treatment, over and above other characteristics that are already known to predict poor participation in treatment. Barriers associated with treatment participation can help identify cases at risk for dropping out and suggest targets for intervention to improve retention of families in treatment.

Family experience of barriers to treatment and premature termination from child therapy

Barriers to participation in treatment were proposed as a basis for dropping out of treatment among children seen in outpatient therapy. Families (N = 242) of children referred for treatment for oppositional, aggressive, and antisocial behavior participated. The main findings were that (a) barriers to participation in treatment contributed significantly to dropping out of therapy; (b) perceived barriers to treatment were not explained by family, parent, and child characteristics that also predicted dropping out; and (c) among families at high risk for dropping out of treatment, the perception of few barriers attenuated risk. Parent perceptions of the difficulties of participating in treatment (including stressors and obstacles associated with treatment, perceptions that treatment is not very relevant, and a poor relationship with the therapist) influenced who dropped out.